It wasn't really a good figure that Apple suffered with the story of the new non-working keyboard on the old Mac USB. To give a release date of a product publicly, to state that it works "with all Macs with USB" and then discover that this does not denote, at least, a great approximation in beta testing, the more unforgivable if the producer of the hardware in question , as in this case, responsible for the production and marketing of all the components involved. Is it possible that Apple didn't think of installing the keyboard even on old iMacs before announcing its compatibility with all USB machines?
But beyond the basic question and which denotes that something has not worked in the marketing mechanism, it does not seem appropriate to make dramas and take for granted that it will be necessary to wait for the release of "new software" (probably the update to MacOs 9.5) which is read on the Apple website to adopt the keyboard. In particular those who, like in Italy, anxiously waited for the device to put their hands literally on a keyboard more comfortable than the current ones. In fact the problems we talk about on the Internet are essentially related to the non-functioning of some non-vital keys. These are "volume up", "volume down", "mute" and "disc eject". Everything else appears to be working perfectly without any problems. The more demanding, then, provided you have MacOs 9.04 installed, could even enable the first three keys using the "USB Device Extension" that can be obtained from a friend who already has the new iMac post New York or by downloading the USB Developer Kit 1.4.3f3 and which contains, in fact, the USB Device Extension. The only problem will be the inability to use the disc eject button. This is not a solution certified by Apple but if you really need to use the new keyboards it is a good way to do it.
Now it remains to be seen for when Apple decides to release the keyboards. On the AppleStore the assembly times are always fixed at 45 days, in practice after the second half of November if we consider the holidays. Certainly this is not a comforting time frame and could lead someone to opt for the ever-increasing alternatives offered by the market.